﻿Shader "Custom/MyShader" {
	Properties {
		[PerRendererData] _MainTex("Sprite Texture", 2D) = "white" {}
		_Color("Tint", Color) = (1,1,1,1)

		_StencilComp("Stencil Comparison", Float) = 8
		_Stencil("Stencil ID", Float) = 0
		_StencilOp("Stencil Operation", Float) = 0
		_StencilWriteMask("Stencil Write Mask", Float) = 255
		_StencilReadMask("Stencil Read Mask", Float) = 255

		_ColorMask("Color Mask", Float) = 15

		//-------------------add----------------------
		_Center("Center", vector) = (0, 0, 0, 0)
		_Silder("_Silder", Range(0,1000)) = 1000 // sliders
		//-------------------add----------------------

		[Toggle(UNITY_UI_ALPHACLIP)] _UseUIAlphaClip("Use Alpha Clip", Float) = 0
	}
	SubShader {
		
		Tags
		{
			"Queue" = "Transparent"
			"IgnoreProjector" = "True"
			"RenderType" = "Transparent"
			"PreviewType" = "Plane"
			"CanUseSpriteAtlas" = "True"
		}

		Stencil
		{
			Ref[_Stencil]
			Comp[_StencilComp]
			Pass[_StencilOp]
			ReadMask[_StencilReadMask]
			WriteMask[_StencilWriteMask]
		}

		Cull Off
		Lighting Off
		ZWrite Off
		ZTest[unity_GUIZTestMode]
		Blend SrcAlpha OneMinusSrcAlpha
		ColorMask[_ColorMask]

		Pass
		{
			Name "Default"
			CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#pragma target 2.0

#include "UnityCG.cginc"
#include "UnityUI.cginc"

#pragma multi_compile __ UNITY_UI_ALPHACLIP

		struct appdata_t
		{
			float4 vertex   : POSITION;
			float4 color    : COLOR;
			float2 texcoord : TEXCOORD0;
			UNITY_VERTEX_INPUT_INSTANCE_ID
		};

		struct v2f
		{
			float4 vertex   : SV_POSITION;
			fixed4 color : COLOR;
			float2 texcoord  : TEXCOORD0;
			float4 worldPosition : TEXCOORD1;
			UNITY_VERTEX_OUTPUT_STEREO

		};

		fixed4 _Color;
		fixed4 _TextureSampleAdd;
		float4 _ClipRect;
		//-------------------add----------------------
		float _Silder;
		float2 _Center;
		//-------------------add----------------------
		v2f vert(appdata_t IN)
		{
			v2f OUT;
			UNITY_SETUP_INSTANCE_ID(IN);
			UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(OUT);
			OUT.worldPosition = IN.vertex;
			OUT.vertex = UnityObjectToClipPos(OUT.worldPosition);

			OUT.texcoord = IN.texcoord;

			OUT.color = IN.color * _Color;
			return OUT;
		}

		sampler2D _MainTex;

		fixed4 frag(v2f IN) : SV_Target
		{
			half4 color = (tex2D(_MainTex, IN.texcoord) + _TextureSampleAdd) * IN.color;

			color.a *= UnityGet2DClipping(IN.worldPosition.xy, _ClipRect);

#ifdef UNITY_UI_ALPHACLIP
			clip(color.a - 0.001);
#endif
			//-------------------add----------------------
			color.a *= (distance(IN.worldPosition.xy,_Center.xy) > _Silder);
			color.rgb *= color.a;
			//-------------------add----------------------
			return color;

		}
		ENDCG
		}
	}
}
